In July 2006 A New Developed High Efficient Solar Heating/natural gas heating system was installed in an old one family house
in Denmark. The new system was based on 6.75 m
2 solar collectors and a condensing natural gas boiler. Before the installation of the solar heating system, the house was
heated by a non condensing natural gas boiler.
The heat demand, the electricity consumption for the energy and heating system as well as the natural gas consumption were
measured before and after installation of the solar heating system. Based on the measurements the energy savings of the solar
heating system were estimated to 4200 kWh per year, corresponding to 620 kWh/m2 collector per year. The energy savings will vary from year to year. In years with a high heat demand the energy savings will
be high. In years with a low heat demand the energy savings will be low.